Belt sander for spiral conveyer rolls



Dec. 20, 1955 T. GRONNING 2,727,338

BELT SANDER FOR SPIRAL CONVEYER ROLLS Filed Jan. 5, 1954 3 Sheets-Sheet 1 FIG] INVENTOR TH OR BJORN GRONNING BY 4m, 41; mam

ATTORNEY! Dec. 20, 1955 GRQNNING 2,727,338

BELT SANDER FOR SPIRAL CONVEYER ROLLS Filed Jan. 5, 1954 3 Sheets-Sheet 2 FIG.2

INVENTOR TH ORBJORN GRONNIN G BMMMM ATTORNEYS Dec. 20, 1955 T. GRONNING 2,727,338

BELT SANDER FOR SPIRAL CONVEYER ROLLS Filed Jan. 5, 1954 3 Sheets-Sheet 5 F I G 3 INVENTOR THORBJORN GRONNING BYQ M M "1W ATTORNEYS United States Patent 6 BELT-SANDER- FOR SPIRAL CON -V I1 YER ROLLS ThorbjornGronning, Seattle, Wash., assignor to Continental'Can, Company, Inc., New York, Y., a corporation of New York Applicationzlanuary 5, .1954, Serial. No. 402,203'.

6 Claims. (Cl. 51-"144) The: following specification relates tonovel improvements in a belt sander forspiral conveyer rollsand the like; In the can handling industries, cans are fed to and from work stations by means ofrotating spiral conveyer rolls. These rolls have concave spiral recesses suitably proportioned to -fitpartially around the cylindrical' side walls of the cans and advance them individually. Theproper and efiicient engagement with the individual cans-and advancing themdepends upon having the spiral concavitiesevenlyspaced from the axis of the rolli andsuitably concave in longitudinal cross-section; That'is, the root'diarneterof the spiral should be at a constant distance'from the axisof the roll or on an even taperthereto.

It has been found thatthespiral concavities or can engagingytracks can most effectively be produced by grinding; along lines which are comparable to the'cylin drical'surface of the cans which it is intended to feed.

One-of the objects of'my invention is to provide a sanding machine by which'the-concave spiral of the feed roll can be ground true.

Another'object of my invention is to provide a work holder which can be manipulated to feed the work into the-desired engagement with the sandingelement.

A further object of .the invention is to provide a sanding machine which may be adjusted to sanding spiral feed rolls of various desired sizes.

Among the objects of my invention is to provide means for giving'a desired taper to the spiral of "a feed roll.

The objects of my invention also include the. pro: visionof guide means which will withdraw the work from the grinding device where the stresses become excessive."

In like manner theinvention includesthe provision of suitable housing and facilities for the control and dis-. posal of dust produced in the. sanding or grinding opera-v IIOIL.

The inventionis best illustrated in its preferredform on.the accompanying drawings in which Fig, lis a plan view of the. improved belt sander with the. covers removed;

Fig, 2 is a, front elevation, and

Fig 3' is .an end elevationofthe same.

The novel deviceconsists of an endlessbelt sander directly driven by a motor. and providing a sanding surface which conforms to, the cylindrical contour of the cans-for which. the. spiral feed rollis intended.- The sanding b'elt is mountedon arotating pulley which: isadjusted'inpositionto give appropriate tension and then locked into position. A.work holder for thespiralnfeed rolliis provided. Thisvis. advanced against the sanding belt so. that they spiral concavity is ground .into across sectionconforming,to., the side wallof the can. In; this operation,,the.work holder. is. held up to -th.e;sanding-: beltby a. guide. rail. which in turn may be'released under abnormal operating conditions. Finally the dust. produced in the sanding-operationis removed; from the area around the-work- In the-drawings Phave shown a table 4; This includes a cast metal top 5, supported on a frame '6.-

The top- 5*hasan opening over which'asupporting plate 7 is bolted: A- motor 8' is suspended beneath the supportingplate 7' with its shaft projecting vertically through-the plate and'above the'top of the table; The shaft ofthe motor carries a driveipulley' 9; Thisis preferably'ofwood-or other like material which does not store energy of rotation to such an, extent as would result in coasting after the motor stops.

The pulley 9. is of: considerable width. It is adapted to carry an endless sanding belt 10; As sanding belts of diiferent widths are required to finishithe spiraldrive rolls of different sizes of cans, the pulley has amaximum width. to accommodate the largestsanding. belt. When a new of less width is, used, a spacing collar 11 is fitted tightly around the upper portion .ofith'e pulley 9;.

The top ofthe table is slotted transversely, as shown at E2 on Fig. 1, along a line whichlis perpendicular toward the front end ofthe table and radial .with respect to the drive pulley 9' This slotted portion 12 forms a track along which a bearing plate 13 and shaft 14. are movable from front torear.

The. vertical, fixed'shaft' 1 4 is mounted in the bearing plate 13and extends bothabove andbelow thetop of thetable.

A boss 15 isformed integrally beneath the top of the table and'at the rightof the. slot 12. This boss forms a. fulcrum for av lever. 16. The short end of the. lever hasan elongated hole fitting-over thefiXed. shaft- 14. below the top of the table. The other end of the. lever is, ex: tended beyond the endof the table .top. and there-provided with a; handle 17. V

The lower end of-thefixed shaft 14 below the; lever 16 is threaded to receive a nut.18v which has an operat; ing handle19, Theshaft-ll is provided with a spacing collar 20:.between: lever 16- and nut 18. Thenut may be locked against the collar 20 and lever 16', clamping the latter against the lower surface of thetable: top and thus locking the. bearing plate '13 in adjusted position.

The, fixed shaft 14. at.its upper. end carries a driven pulley 21..which has a metal bushing in contact with the fixed shaft. Lubricationfor the bushing, on. the fixed shaft.1 .4 is provided centrally of the shaft by means of the, nipple. 22..

Both pulleyshavefrictional outer surfaces madeof rubber gasket material, or the like.

A guiderail.2 3:.is pivoted on bolt 24 at the left end of the .top ofthetable. The guide rail hasa vertical flange 3.7 onitsinner edge. The rail 23 extends, beyond the right end of thetable where it is provided with a-depending,; apertured end 25.

Thisend of the. table is provided with a screw-threaded b1ock,26 in the same. plane with the apertured end 25.

Anadjustment screw. 27 passes through they apertured depending. end 25; and is1screw-threaded: into theblock 26.. Two nuts. 3.6, 36 aretightenedtogether on thescrew 27; to. form an adjustable stop; against which the depending end'25 rests. i

In. front of the end..25.,.thescrew;27- isprovided with a helicallcompression spring 28; Ahand. wheel29 forms the end ofjthe'screw 27,so .that.tl 1e,spring-28 rests against the hand 'wheel and. maintains. compressionagainst the depending end 25 holding the. latter against. the nuts-36,. 36;

The conveyer rolllis shown-at3ll on Fig. l toinclude. a helix '3l. This'helix or spiral musthe trued'by, the sanding belt so that its cross-section 0n thelongitudinal axis will conform to the side wall of the can of selected dimension. The-conveyer -roll is -provided'with operating handles 32, 32, axially at each end. These handles are held in the ends 33, 33 of a carriage 34.

Where it is desired to provide a suitable taper for the rolls, one end of the carriage 34 is provided with a plate 35 having a roll which rests against the front flange 37 of the guide rail 23, the adjustment of the roll determining the degree of taper.

As the work requires that the operator use both hands in holding it, the operation of the motor is made dependent upon an operating foot switch 38. This switch 38 is mounted between parallel links 39, 39, hinged to the frame and lowered to the floor for foot operation. When desired, the links may be raised so that the foot switch is out of working or operating position.

A reversing switch 40 is provided at the left end of the frame. In this manner the motor 8 may be put in operation by the foot switch in either direction, determined by the reversing switch.

Suitable housing is provided over and around the sanding belt and both pulleys. A hood 41 is hinged at the back at 42 and extends up and over the drive pulley 9, enclosing it on both sides as well. A post 43 extends upwardly from the table in front of the drive pulley 9 and passes through the front of the hood.

Dust guards 44, 44 are screwed on to the table top on v each side of the driven pulley 21 and can be adjusted from front to back, as shown in Fig. l. Suction ducts 45, 45 lead out from the guards 44, 44 and are connected by suitable means to a source of suction.

A cover 46 is provided over the dust guards 44, 44. Thiscover is open in front but has a top that extends back and over the front of the hood 41, as shown in Fig. 3. A wing-nut 47 serves to hold down the hood 41 and the cover 46 on the end of the post 43.

Dependent upon the diameter of the can or other cyl inder to be transferred by the conveyer rolls, either a narrow or wide sanding belt will be selected. A narrow sanding belt three inches wide is used for cans of smaller diameter. This will do for cans having dimensions of sizes 202 to 404. A five inch belt is required for larger spirals suitable for larger cans.

The width of the driven pulley 21 is thus determined. In like manner, the length of the fixed shaft 14 and the spacing collar 11 are also dependent upon the width of the sanding belt.

The screw 27 admits of a fine adjustment. The provision of the safety arrangement enables the operator to back the work piece quickly away from the belt when sanding high spots, or when the belt is slipping.

An adjustable taper attachment is provided at the end of the carriage so that the root of the spiral can be adjusted. For larger spirals, a separate carriage with a fixed taper can be provided. By manual feeding of the work piece, from 0.015" to 0.030" of material can be removed in a single operation. As the area of contact with the belt becomes greater, less feed can be applied.

The sanding belt can also be used on flat surfaces.

It will readily be understood that with the sanding belt in operation, the carriage will advance the spiral roll with the belt in contact with the spiral groove. The roll is advanced from right to left, being gradually rotated by the handles provided. This will produce any desired taper or even parallelism, if it is desired. Any undue tension on the belt or work will be relieved by the spiral spring 28.

The operation of the motor is under control constantly by means of the foot pedal and switch. Reversing the belt can be eifected by use of the reversing switch.

While'the invention has been illustrated and described by way of example, it may be embodied in structures having different sizes, proportions and materials. For this reason the invention is to be limited only in scope by the following claims.

What I claim is: r

1. In combination, a table having a mounting portion, a motor suspended from said portion, a driving pulley on the motor shaft above the table, a bearing 1 tion, a motor suspended from said portion, a driving pulley on the'motor shaft above the table, a bearing plate adjustable on the' table to and from the driving pulley, a driven pulley rotatably carried on the bearing plate, an endless sanding belt on said pulleys, a guide rail on the table opposite the driven pulley and in a plane perpendicular to the axis of the pulley, said rail being pivoted at one end to the table and held adjustably andresiiiently at its other end, and a work-holding carriage movable along the table between the driven pulley and the guide rail.

3. In combination, a table having a mounting portion, a motor suspended from said portion, a driving pulley on the motor shaft above the table, a bearing plate slidable in the table top to and from the driving pulley, a lever for moving the bearing plate, a clamp for locking the bearing plate and lever to the table top, a fixed vertical shaft on the bearing plate, a driven pulley rotatably mounted on the fixed shaft, an endless sanding belt on said pulleys, a guide rail on the table opposite the driven pulley, said rail being pivoted at one end to the table and held adjustably and resiliently at its other end, and a work-holding carriage movable along the table between the driven pulley and the guide rail.

4. In combination, a table having a mounting portion, a motor suspended from said portion, a driving pulley on the motor shaft above the table, a bearing plate slidable in the table top to and from the driving pulley, a fixed vertical shaft extending through the bearing plate, a lever pivoted below the table top and having one end intersected by the lower portion of the vertical shaft, a nut screw-threaded on said portion of the shaft for clamping the bearing plate and lever to the table top, a driven pulley rotatably mounted on the fixed shaft, an endless sanding belt on said pulleys, a guide rail on the tableopposite the driven pulley, said rail being pivoted at one end to the table and held adjustably and resiliently at its other end, and a workholding carriage movable along the table between the driven pulley and the guide rail.

5. In combination, a table having a mounting portion, a motor suspended from said portion, a driving pulley on the motor shaft above the table, a bearing plate adjustable on the table to and from the driving pulley,

a driven pulley rotatably carried on the bearing plate, an endless sanding belt on said pulleys, a guide rail on the table opposite the driven pulley and in a plane perpendicular to the axis of the pulley, and a Work-holding carriage movable along the table between the driven pulley and the guide rail, said carriage having a roller at one end to adjust the inclination of the axis of the work piece to the line of travel past the sanding belt.

6. In combination, a table having a mounting portion, a motor suspended from said portion, a driving pulley on the motor shaft above the table, a bearing plate slidable in the table top to and from the driving pulley, a lever for moving the bearing plate, a clamp for locking the bearing plate and lever to the table top, a fixed vertical shaft on the bearing plate, a driven pulley rotatably mounted on the fixed shaft, an endless sanding belt on said pulleys, a guide rail pivoted at one end on the table top opposite the driven pulley, a resilient adjustable holder for the opposite end of the rail, a work-holding carriage slidable along the table between the driven pulley and the guide rail, dust guards lateral- 5 6 1y disposed on opposite sides of the sanding belt, suc- 679,611 Ensign July 30, 1901 tion pipes leading from said guards, a hood over the 1,286,560 Docter Dec. 3, 1918 driving pulley and belt, a cover over the dust guards 1,701,814 Maddox Feb. 12, 1929 and driven pulley, and a foot-operated switch for th 2,261,614 Buckley Nov. 4, 1941 motor. 5 2,531,921 Schultz Nov. 28, 1950 I 2,639,561 Aspinall May 26, 1953 References Cliedlll the file A0; his patent FOREIGN PATENTS UNITED slATES P NTS 216,224 Great Britain May 26, 1924 557,462 Wenchel Mar. 31, 1896 10 624,882 Unkrich May 9, 1899 

